SequenceFileUtility.java 文件源码

@SuppressWarnings("unchecked")
private Writer createWriter(Map<String, String> metadata) throws IOException {
    final Metadata md = new Metadata();

    for (final Entry<String, String> e : metadata.entrySet()) {
        md.set(new Text(e.getKey()), new Text(e.getValue()));
    }
    final Class<K> keyClass = (Class<K>) ((ParameterizedType) getClass().getGenericSuperclass())
            .getActualTypeArguments()[0];
    final Class<V> valueClass = (Class<V>) ((ParameterizedType) getClass().getGenericSuperclass())
            .getActualTypeArguments()[1];

    return SequenceFile.createWriter(fileSystem, config, sequenceFilePath, keyClass, valueClass, compressionType,
            new DefaultCodec(), null,
            md);
}